Sounding horn



Feb. 21, 1933. E HEWITT 1,898,536

SOUNDING HORN Filed Jan. 29, 1932 Fig. l 8 O 4 IN VENTOR.

ELL! 5 E. HEWITT .4 TTORLVEY.

Patented Feb. '21, 1933 AUNITED- STATES PATENT OFFICE ELLIS E. HEWITT, OF EDGEWOOD, PENNSYLVANIA, ASSIGNOB TO THE WESTINGHOUSE AIR BRAKE COMPANY, OF WILKERDING, PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA sormnmo HORN Application filed January 29, 1932. Serial No. 589,638.

This invention relates to pneumatic signal pneumatic signal horn wherein the vibrating diaphragm or disc is supported at a single point near the peripheral edge thereof and wherein the disc is retained in centered operative position by the cap covering the disc.

Another object of the invention is to provide a pneumatic signal horn having the above noted characteristics, wherein the means for centering the vibrating discs are disposed remote from the center thereof and consequently do not interfere with a tone adjustment means aligned axially with the disc and which is operable from the exterior of the diaphragm casing.

A further object of the invention is to provide a multi-tone signal horn having a com mon means for centering and supporting the plurality of vibrating sound producing discs in such manner that they are free to vibrate independently and at different frequencies.

A further object of the invention is to provide a multi-tone or multi-disc pneumatic horn, wherein a plurality of vibrating discs,

each disposed within a separate chamber, are centered by a common supporting means.

A further object of the invention is to provide a multi-tone signal horn, wherein the vibrating discs may be formed in a single piece from sheet metal and centered by a single supporting means.

A further object of the invention is to simplify the construction of a pneumatic signal horn and thereby reduce the cost of manufacture.

These and other objectsthat will be made apparent throughout a further description of the invention are attained by means of the signal horn hereinafter described and illustrated in the accompanying drawing; wherein Fig. 1 is a sectional view of a signal horn embodying features of my invention;

Fig. 2 is a transverse sectional view of the device shown in Fig. l-taken on the line 22 thereof; and

'Fig. is a fragmental sectional view of the device shown in Fig. 1 taken on the line 3-3'thereof.

Referring to the drawing, the signal horn may comprise a casing 4 having a pair of chambers 5 and 6 connected by a channel or groove 7' (Fig. 3) and each having a reduced bore 8, in which the usual sound amplifying horn 9 is secured. Surrounding the reduced bore 8 of each chamber is a seat rib 10, the purpose of which will hereinafter appear.

The chambers 5 and 6 are closed by a cap or cover 11 having a. centrally disposed web 12, that extends into and completely seals the channel or groove 7 in the casing, and which serves as a clamping means for securing the vibrating discs of the separate horn chambers in centered position.

The circular vibrating discs 13 and 14 are integrally joined by a flexible tongue or strap 15, which fits within the groove 7 and which is held against lateral and. angular displacement by a pair of dowel pins 16 mounted'in the casing 4 and which extend through perforations in the tongue 15 and into dowel bores 17 in the cap 11. The web 12 tightly engages the tongue 15 when the cap 11 is secured in place by the screws 18. It is apparent, therefore, that two separate horn chambers 5 and 6 are provided in which the circular diaphragms or discs 13 and 14 are respectively so mounted within the chambers 5 and 6 that they rest upon the seat ribs 10 and yieldingly close communication between the said chambers and the reduced bores 8 thereof containing the amplifying horns 9.

The vibrating discs 13 and 14 are yieldingly pressed into engagement with the seat ribs 10 by means of springs 19, which are disposed between the diaphragms 13 and 14 and flanged centering sleeves 21, that are swiv elled upon adjusting screws 22 threaded in the cap 11 and locked in place by lock nuts 23. Each spring 19 is centered upon its re spective disc by a weighted stud 24 that is secured to the center of the vibrating disc by a rivet 25.

Communication is established between the the chambers 5 and 6 when a valve (not shown) in the pipe 28 is open. When the pressure in the chambers 5 and 6 is reduced sufiiciently below atmospheric pressure pres- 10 cut in the bores 8,. the diaphragms or discs 13 and 14 are moved away from the seat ribs 10 against the tension of the springs 19. Air immediately flows into the chambers 5 and 6 past the seat ribs 10 and increases the pressure in the chambers 5 and 6 suificiently to permit the springs 19 to again move the discs 13 and 14 into contact with seat ribs 10. A When the pressure in the chambers 5 and 6' again falls, the discs 13 and 14 are again moved to open position and the operation is repeated at arfrequency depending upon the tension ofthe springs 19. The frequency of vibration is of such magnitude that an audible musical tone is produced by each diaphragm and when the springs 19 areadj usted to oppose opening movement of the discs 13 and 14 with diflerent forces, the discs 13 and 14 are, respectively, caused to produce sounds of different tone. By reason of the adjustment screws, the horns may be adjusted to produceharmonious tones pleasing to the car.

It is apparent from the foregoing that the construction of the signalhorn is simple and the parts are of such character that they may be readily assembled, and since the adjustment screws are accessibleirom the exterior of the casing, any desiredtone may be obtained without necessitating the removal of any part of the device.

While I have, for the purpose of illustra-' tion, disclosed the invention as a double signal horn device, it is obvious that three or more horns may be mounted in the same casing and the vibrating discs thereof supported and centered by a common supporting means. It is also apparent that many changes may be made in the construction without departing from the spirit of the invention.

Having now described my invention, what I claim as new and desire to secure by Le ters Patent, is: I

1. In a sound producing device, the com bination with a pair of adjacently disposed.

vibrating discs and means for causing vibration of the discs by variations in fluid pressure acting thereon, of an integral connecting member extending between adjacent edge portions of the discs for supporting the respective discs at single points adjacent their periphery and permittingvibration of the sai 2. A sound producing device comprising a casing a chamber, a cover therefor, a sound generating disc mounted in said chamber and adapted to engage a seat provided in the casing, said disc being caused to vibrate by variations in fluid pressure in the chamber at one side of the disc, and means including the cover for clamping the disc at a single point adjacent its periphery and permitting vibration of the disc, but preventing lateral displacementthereof.

3. A sound producing device comprisin a casing having a. chamber, a cover there or,

.a sound generating disc mounted in said chamber and adapted to engage a seat provided in the casing,'said disc being caused to vibrate by variations in fluid presure in the chamber at one side of the disc, and positioning means for the discincluding the.

5, A sound producmg device comprising a casing having a chamber, a sound eneratmg disc mounted in said chamber an adapted to engage a seat provided in the casing, and having a tongue extending beyond the peripheral edge of the disc, said disc bemg caused to vibrate by variations in fluid pressure in the chamber at one side of the disc, and acap for the said chamber and engaging the said tongue for clamping the disc in operative position between the said cap and said casing.

6. A sound producing device comprising a casing having a chamber, a sound generatin disc mounted in said chamber and adapted to engage a seat provided in the casin said disc being caused to vibrate by varlations in fluid pressure in the chamber atone side of the disc, a cap for the said chamber and engaging a portion of the said disc at a point eccentric to the disc, a spring aligned axially with the disc and disposed between the disc and the cap for regulating the frequency of vibration of the disc and carried by the cap, and means operable exteriorly thereof for varying the tension of the said spring.

' 7. A sound producing device comprising a casing having a chamber, a sound generating disc mounted in said chamber and adapted to engage a seat provided in the casing, said disc being caused to vibrate by variations in fluid pressure in the chamber at one side of vibration'of the disc and carried by the cap,

and an adjusting screw carried by the cas and aligned axially with the said disc an operable exteriorly of the cap for varying the tension of the said spring.

8. In a sound producing device, a plurality of fluid actuated eccentrically disposed vibrating discs, and a common means for centering the discs in their respective positions.

9. In a sound producing device, a plurality of integrally joined vibrating discs.

10. In a sound producing device, a plurality of integrally oined vibrating discs, and a common means for centering the discs.

11. In a sound producing device, a plurality of sound chambers, a vibrating disc in each chamber, and means common to all of the discs for centerin them.

11 testimony where of I have hereunto set my hand, this 25th day of January, 1932. ELLIS E. HEWITT. 

